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The Great Migration from MongoDB to PostgreSQL

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Re: The Great Migration from MongoDB to PostgreSQL

#81

Post by ako »

endisneigh wrote: post #77
ako wrote: post #76

Earlier quoted context omitted.

And that’s the core problem with key value stores, your data needs usually grow beyond key value scenarios. In the beginning it might fit, but then you add more pages with different needs, reporting/dashboards with different needs, APIs with different needs, and ETL processes with different needs. Trying to force everything into key value is short term thinking.

What you’re describing isn’t an inherent problem with a key value store. Forcing everything to OLTP SQL is also short term thinking. Pick the right tool for the job. It’s funny you mention growth as the limiting factor for key value stores, if anything that’s the one area where they’re objectively superior. Which is why most search databases and caches are key value stores.

Not if you use a rdbms to store your key/values. Then you can do arbitrary queries with joins over multiple tables, add views, stored procedures, etc.

Re: The Great Migration from MongoDB to PostgreSQL

#82

Post by endisneigh »

ako wrote: post #81
endisneigh wrote: post #77

Earlier quoted context omitted.

What you’re describing isn’t an inherent problem with a key value store. Forcing everything to OLTP SQL is also short term thinking. Pick the right tool for the job. It’s funny you mention growth as the limiting factor for key value stores, if anything that’s the one area where they’re objectively superior. Which is why most search databases and caches are key value stores.

Not if you use a rdbms to store your key/values. Then you can do arbitrary queries with joins over multiple tables, add views, stored procedures, etc.

Sure, but that’s not related to what you said prior. Again, right tool for the job.

Re: The Great Migration from MongoDB to PostgreSQL

#83

Post by cj »

KingOfCoders wrote: post #48

Some years ago we had so much problems with MongoDB that we also ditched it for Postgres. Never been happier. Not the reason, but very annoying: Why doesn't (perhaps this has changed?) MongoDB use SQL but Javascript with endless $s? It was always a pain writing ad-hoc queries.

> Why doesn't MongoDB use SQL

Perhaps not the right answer, but SQL literally stands for Structured Query Language. I suppose you'd need an USQL?

Re: The Great Migration from MongoDB to PostgreSQL

#84

Post by pydry »

onetimeuse92304 wrote: post #38

Ah, the old "I used a wrong product for my problem and now I complain the product is bad because it does not suit my case." defence. MongoDB is a document database. It is not supposed to be good at relations. Also lacking support with cloud providers and lacking experience with MongoDB is not MongoDB's problem, it is your poor decisionmaking. If you value those things, you should have taken it into account when you w…

The issue isn't that mongodb isn't suitable for some problems. I've used it before and it has not caused issues. It's that the problems it is suitable for are a subset of those that postgres is suitable for.

I can just as easily rapidly prototype in postgres. If I want to store schemaless JSON in postgres I can easily do that.

>In the end, I think it is good to have a selection of tools that are good at doing different things.

In the end I think every tool needs a niche - something it is good at that its competing tools are not good at.

Mongo doesnt have that.

Re: The Great Migration from MongoDB to PostgreSQL

#85

Post by andybak »

iambateman wrote: post #65

I use MySQL for everything - always have. Can someone hit me with a few reasons why you would use Postgres over MySQL? I don’t have any familial affinity to any database, but I’m not sure what the benefits to Postgres are relative to MySQL.

PostGIS was way ahead of the MySQL equivalent last time I checked.

The plugin ecosystem is pretty astonishing. Foreign Data Wrappers... I'm not hands on so much any more but there were a lot of things back when I was.

Re: The Great Migration from MongoDB to PostgreSQL

#86

Post by Beefin »

jpgvm wrote: post #45

I have done this migration twice and rethinkdb to PostgreSQL once. At this point I think document DBs are as good as dead for new projects. They will live for a really long time still but are in contraction and rent seeking mode now. Expect MongoDB licensing and hosting to increase in price and languish in terms of feature development from here on out.

mongodb is a fortune 100 company and blows through expectations every quarter. doc dbs are far from dead.

Re: The Great Migration from MongoDB to PostgreSQL

#87

Post by CuriouslyC »

onetimeuse92304 wrote: post #38

Ah, the old "I used a wrong product for my problem and now I complain the product is bad because it does not suit my case." defence. MongoDB is a document database. It is not supposed to be good at relations. Also lacking support with cloud providers and lacking experience with MongoDB is not MongoDB's problem, it is your poor decisionmaking. If you value those things, you should have taken it into account when you w…

If mongo is just a document database, there's really no reason to use it over elastic. The query story is slightly nicer with mongo, but we're not doing relational algebra here, right? Elastic crushes mongo at literally everything else.

Re: The Great Migration from MongoDB to PostgreSQL

#88

Post by rb12345 »

SonOfLilit wrote: post #46
bandrami wrote: post #34

Earlier quoted context omitted.

I think the sense is not "atomic by field" or whatever you'd call that. If you're going to ignore the fact that PG is an actual ORDB and just store gigantic blobs of JSON in it, it will write the entire object whenever you update part of it, because the whole point is you're supposed to store it as a multi-field record.

Isn't that true for Mongo as well?

Yes, but as MongoDB is a document database, storing and updating giant blobs of JSON as a single operation as opposed to breaking the JSON down into individual fields is intended behaviour. This works in Postgres too, of course, but then you lose the relational database advantages on top of the large-single-field issues.

All this really comes down to is picking the right database type for the problem you're trying to solve.

Re: The Great Migration from MongoDB to PostgreSQL

#89

Post by wlll »

iambateman wrote: post #65

I use MySQL for everything - always have. Can someone hit me with a few reasons why you would use Postgres over MySQL? I don’t have any familial affinity to any database, but I’m not sure what the benefits to Postgres are relative to MySQL.

I do scaling and performance work, mostly with Rails apps, but a significant amount of the work is database level and not language specific. I've used both postgres and MySQL (and a few other databases) going back to 2000.

The best thing I can hear from a company when I start is "We use Postgres". If they're using postgres then I know there's likely a far smoother path to performance than with MySQL. It has better tooling, better features, better metadata.

Re: The Great Migration from MongoDB to PostgreSQL

#90

Post by wesselbindt »

pydry wrote: post #80
rjbwork wrote: post #59

Earlier quoted context omitted.

He's always been fundamentally a salesman. Hopping on the hype trains lets him sell more.

He's always been fundamentally a zealot who sees most narratives in black and white terms. It's an extremely unfortunate characteristic of a software engineer. It's the same reason he's so pro Trump I think.

The reason he says he voted for Trump is taxes. But that seems like a pretty flimsy reason. Have dems in the past couple decades ever reverted any republican-instated tax cuts for the wealthy/corporations, or even made any moves for tax bumps? In my experience dems are just republicans, except they wave a rainbow flag every now and then.
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